ref: 36b24a92d94b1d1f100746d27d13fc77f1599201
dir: /3rd/mp/u16.c/
#include "platform.h" #define between(x,min,max) (((min-1-x) & (x-max-1))>>8) int enc16chr(int o) { int c; c = between(o, 0, 9) & ('0'+o); c |= between(o, 10, 15) & ('A'+(o-10)); return c; } mpdigit dec16chr(int c) { int o; o = between(c, '0', '9') & (1+(c-'0')); o |= between(c, 'A', 'F') & (1+10+(c-'A')); o |= between(c, 'a', 'f') & (1+10+(c-'a')); return o-1; } int dec16(uint8_t *out, int lim, char *in, int n) { int c, w = 0, i = 0; uint8_t *start = out; uint8_t *eout = out + lim; while(n-- > 0){ c = dec16chr(*in++); if(c < 0) continue; w = (w<<4) + c; i++; if(i == 2){ if(out + 1 > eout) goto exhausted; *out++ = w; w = 0; i = 0; } } exhausted: return out - start; } int enc16(char *out, int lim, uint8_t *in, int n) { uint32_t c; char *eout = out + lim; char *start = out; while(n-- > 0){ c = *in++; if(out + 2 >= eout) goto exhausted; *out++ = enc16chr(c>>4); *out++ = enc16chr(c&15); } exhausted: *out = 0; return out - start; }